Convert wareki years on Japanese forms without a lookup table

平成5年 is which Gregorian year? Forms for resumes, applications, and registrations still ask in wareki. Boundary years trip everyone up — here is how to get them right.

Tools used in this guide

The job

A form asks for your date of birth in wareki, or a contract is dated 平成31年 and you need the Gregorian year for your records. The wareki converter goes both directions and handles the awkward years for you.

Worked example: a birthday on a resume

Born March 15, Heisei 5? Choose “Wareki → Gregorian”, pick 平成 / Heisei, enter 5, 3, 15. Result: March 15, 1993. Going the other way, 1993-03-15 converts to 平成5年3月15日.

The boundary years that trip people up

Era changes happen mid-year, so one Gregorian year can contain two era years. 1989 is both Shōwa 64 (until January 7) and Heisei 1 (from January 8). 2019 is Heisei 31 until April 30, then Reiwa 1 from May 1. The converter's year mode lists every era a Gregorian year contains — check it instead of guessing when a date sits near a boundary.

2019-04-30 → Heisei 31-04-30; 2019-05-01 → Reiwa 1-05-01.
Era year 1 is conventionally written 元年 — the tool accepts both 元 and 1.

Limits

Coverage starts at 1868-10-23, the beginning of Meiji. Earlier historical dates (Edo-era nengō like 慶応) are outside the tool's range. Dates are processed in your browser; nothing is sent anywhere.